Dog Owner's Home Veterinary Handbook.pdf - Mr. Walnuts

FLEA ALLERGY DERMATITIS
This is the most common allergy in dogs. It is caused by a hypersensitivity
reaction to one or more substances in the saliva of fleas. Flea allergy dermatitis
is an allergic reaction of both the immediate and delayed type; itching
begins immediately and tends to persist long after fleas have been eliminated.
One bite is enough to trigger this reaction. Symptoms are worse in midsummer
during the flea season. However, dogs who live in the house may suffer all
year long if fleas are present.
Flea allergy dermatitis is characterized by severe itching with inflamed skin
and red papules found where fleas are heavily concentrated—over the rump
and base of the tail, under the legs, and on the groin and belly. Dogs chew and
rub at these areas. Hair falls out and the skin becomes dry and scaly. In some
cases the skin breaks down and develops raw areas that become crusted and
infected. In time, the skin becomes thick and darkly pigmented.
The diagnosis can be suspected by finding fleas on the dog and seeing the
characteristic skin rash. Check for fleas by standing your dog over a sheet of
white paper and brushing the coat. White and black grains of sandy material
that drop onto the paper are flea eggs and feces. An allergic response to flea
saliva can be confirmed with an intradermal skin test.
Treatment: The majority of dogs with flea allergy dermatitis can be cured
by eliminating fleas on the dog and controlling fleas in the environment. All
pets in the household, even those who are not affected, must be treated simultaneously
to eliminate fleas. Antihistamines and/or corticosteroids may be
required for two to three days to control itching. A medicated bath may also
help to make your dog more comfortable.
Pyoderma requires topical and
oral antibiotics. Seek veterinary
attention for these problems.
Prevention: The monthly application
of a flea-control product, such as
Frontline Plus or Advantage, will kill
adult fleas before they bite the dog.
Program inhibits reinfestation by preventing
fleas from reproducing. The
combination of Program with
Frontline or Advantage should eventually
eliminate fleas, but for a more
rapid response it may be necessary to
treat the environment as described in
Eliminating Fleas on the Premises, page
122.
THE SKIN AND COAT • 137
Hair loss over the rump, thighs, and
belly due to excessive itching, scratching,
and rubbing caused by flea bites.